1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for UniPhier AIDET (ARM Interrupt Detector)
4  *
5  * Copyright (C) 2017 Socionext Inc.
6  *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/init.h>
11 #include <linux/irq.h>
12 #include <linux/irqdomain.h>
13 #include <linux/kernel.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/of_irq.h>
17 #include <linux/platform_device.h>
18 #include <linux/spinlock.h>
19 
20 #define UNIPHIER_AIDET_NR_IRQS		256
21 
22 #define UNIPHIER_AIDET_DETCONF		0x04	/* inverter register base */
23 
24 struct uniphier_aidet_priv {
25 	struct irq_domain *domain;
26 	void __iomem *reg_base;
27 	spinlock_t lock;
28 	u32 saved_vals[UNIPHIER_AIDET_NR_IRQS / 32];
29 };
30 
31 static void uniphier_aidet_reg_update(struct uniphier_aidet_priv *priv,
32 				      unsigned int reg, u32 mask, u32 val)
33 {
34 	unsigned long flags;
35 	u32 tmp;
36 
37 	spin_lock_irqsave(&priv->lock, flags);
38 	tmp = readl_relaxed(priv->reg_base + reg);
39 	tmp &= ~mask;
40 	tmp |= mask & val;
41 	writel_relaxed(tmp, priv->reg_base + reg);
42 	spin_unlock_irqrestore(&priv->lock, flags);
43 }
44 
45 static void uniphier_aidet_detconf_update(struct uniphier_aidet_priv *priv,
46 					  unsigned long index, unsigned int val)
47 {
48 	unsigned int reg;
49 	u32 mask;
50 
51 	reg = UNIPHIER_AIDET_DETCONF + index / 32 * 4;
52 	mask = BIT(index % 32);
53 
54 	uniphier_aidet_reg_update(priv, reg, mask, val ? mask : 0);
55 }
56 
57 static int uniphier_aidet_irq_set_type(struct irq_data *data, unsigned int type)
58 {
59 	struct uniphier_aidet_priv *priv = data->chip_data;
60 	unsigned int val;
61 
62 	/* enable inverter for active low triggers */
63 	switch (type) {
64 	case IRQ_TYPE_EDGE_RISING:
65 	case IRQ_TYPE_LEVEL_HIGH:
66 		val = 0;
67 		break;
68 	case IRQ_TYPE_EDGE_FALLING:
69 		val = 1;
70 		type = IRQ_TYPE_EDGE_RISING;
71 		break;
72 	case IRQ_TYPE_LEVEL_LOW:
73 		val = 1;
74 		type = IRQ_TYPE_LEVEL_HIGH;
75 		break;
76 	default:
77 		return -EINVAL;
78 	}
79 
80 	uniphier_aidet_detconf_update(priv, data->hwirq, val);
81 
82 	return irq_chip_set_type_parent(data, type);
83 }
84 
85 static struct irq_chip uniphier_aidet_irq_chip = {
86 	.name = "AIDET",
87 	.irq_mask = irq_chip_mask_parent,
88 	.irq_unmask = irq_chip_unmask_parent,
89 	.irq_eoi = irq_chip_eoi_parent,
90 	.irq_set_affinity = irq_chip_set_affinity_parent,
91 	.irq_set_type = uniphier_aidet_irq_set_type,
92 };
93 
94 static int uniphier_aidet_domain_translate(struct irq_domain *domain,
95 					   struct irq_fwspec *fwspec,
96 					   unsigned long *out_hwirq,
97 					   unsigned int *out_type)
98 {
99 	if (WARN_ON(fwspec->param_count < 2))
100 		return -EINVAL;
101 
102 	*out_hwirq = fwspec->param[0];
103 	*out_type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
104 
105 	return 0;
106 }
107 
108 static int uniphier_aidet_domain_alloc(struct irq_domain *domain,
109 				       unsigned int virq, unsigned int nr_irqs,
110 				       void *arg)
111 {
112 	struct irq_fwspec parent_fwspec;
113 	irq_hw_number_t hwirq;
114 	unsigned int type;
115 	int ret;
116 
117 	if (nr_irqs != 1)
118 		return -EINVAL;
119 
120 	ret = uniphier_aidet_domain_translate(domain, arg, &hwirq, &type);
121 	if (ret)
122 		return ret;
123 
124 	switch (type) {
125 	case IRQ_TYPE_EDGE_RISING:
126 	case IRQ_TYPE_LEVEL_HIGH:
127 		break;
128 	case IRQ_TYPE_EDGE_FALLING:
129 		type = IRQ_TYPE_EDGE_RISING;
130 		break;
131 	case IRQ_TYPE_LEVEL_LOW:
132 		type = IRQ_TYPE_LEVEL_HIGH;
133 		break;
134 	default:
135 		return -EINVAL;
136 	}
137 
138 	if (hwirq >= UNIPHIER_AIDET_NR_IRQS)
139 		return -ENXIO;
140 
141 	ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
142 					    &uniphier_aidet_irq_chip,
143 					    domain->host_data);
144 	if (ret)
145 		return ret;
146 
147 	/* parent is GIC */
148 	parent_fwspec.fwnode = domain->parent->fwnode;
149 	parent_fwspec.param_count = 3;
150 	parent_fwspec.param[0] = 0;		/* SPI */
151 	parent_fwspec.param[1] = hwirq;
152 	parent_fwspec.param[2] = type;
153 
154 	return irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
155 }
156 
157 static const struct irq_domain_ops uniphier_aidet_domain_ops = {
158 	.alloc = uniphier_aidet_domain_alloc,
159 	.free = irq_domain_free_irqs_common,
160 	.translate = uniphier_aidet_domain_translate,
161 };
162 
163 static int uniphier_aidet_probe(struct platform_device *pdev)
164 {
165 	struct device *dev = &pdev->dev;
166 	struct device_node *parent_np;
167 	struct irq_domain *parent_domain;
168 	struct uniphier_aidet_priv *priv;
169 
170 	parent_np = of_irq_find_parent(dev->of_node);
171 	if (!parent_np)
172 		return -ENXIO;
173 
174 	parent_domain = irq_find_host(parent_np);
175 	of_node_put(parent_np);
176 	if (!parent_domain)
177 		return -EPROBE_DEFER;
178 
179 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
180 	if (!priv)
181 		return -ENOMEM;
182 
183 	priv->reg_base = devm_platform_ioremap_resource(pdev, 0);
184 	if (IS_ERR(priv->reg_base))
185 		return PTR_ERR(priv->reg_base);
186 
187 	spin_lock_init(&priv->lock);
188 
189 	priv->domain = irq_domain_create_hierarchy(
190 					parent_domain, 0,
191 					UNIPHIER_AIDET_NR_IRQS,
192 					of_node_to_fwnode(dev->of_node),
193 					&uniphier_aidet_domain_ops, priv);
194 	if (!priv->domain)
195 		return -ENOMEM;
196 
197 	platform_set_drvdata(pdev, priv);
198 
199 	return 0;
200 }
201 
202 static int __maybe_unused uniphier_aidet_suspend(struct device *dev)
203 {
204 	struct uniphier_aidet_priv *priv = dev_get_drvdata(dev);
205 	int i;
206 
207 	for (i = 0; i < ARRAY_SIZE(priv->saved_vals); i++)
208 		priv->saved_vals[i] = readl_relaxed(
209 			priv->reg_base + UNIPHIER_AIDET_DETCONF + i * 4);
210 
211 	return 0;
212 }
213 
214 static int __maybe_unused uniphier_aidet_resume(struct device *dev)
215 {
216 	struct uniphier_aidet_priv *priv = dev_get_drvdata(dev);
217 	int i;
218 
219 	for (i = 0; i < ARRAY_SIZE(priv->saved_vals); i++)
220 		writel_relaxed(priv->saved_vals[i],
221 			       priv->reg_base + UNIPHIER_AIDET_DETCONF + i * 4);
222 
223 	return 0;
224 }
225 
226 static const struct dev_pm_ops uniphier_aidet_pm_ops = {
227 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(uniphier_aidet_suspend,
228 				      uniphier_aidet_resume)
229 };
230 
231 static const struct of_device_id uniphier_aidet_match[] = {
232 	{ .compatible = "socionext,uniphier-ld4-aidet" },
233 	{ .compatible = "socionext,uniphier-pro4-aidet" },
234 	{ .compatible = "socionext,uniphier-sld8-aidet" },
235 	{ .compatible = "socionext,uniphier-pro5-aidet" },
236 	{ .compatible = "socionext,uniphier-pxs2-aidet" },
237 	{ .compatible = "socionext,uniphier-ld11-aidet" },
238 	{ .compatible = "socionext,uniphier-ld20-aidet" },
239 	{ .compatible = "socionext,uniphier-pxs3-aidet" },
240 	{ /* sentinel */ }
241 };
242 
243 static struct platform_driver uniphier_aidet_driver = {
244 	.probe = uniphier_aidet_probe,
245 	.driver = {
246 		.name = "uniphier-aidet",
247 		.of_match_table = uniphier_aidet_match,
248 		.pm = &uniphier_aidet_pm_ops,
249 	},
250 };
251 builtin_platform_driver(uniphier_aidet_driver);
252